%I #9 Jul 10 2022 08:20:59
%S 0,1,2,720,620448401733239439360000
%N (n!)!, n>0 (note that A000197 is the correct version of this sequence, with a(0) = 1, not 0).
%K nonn,easy
%O 0,3
%A _N. J. A. Sloane_.